SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e909a91f4773be8a4d695cfee84299aacf86722a0029e5ab65047e512d24561' 
  AND token = 'Zi84DBTrfb6fARNCrIEH8qWGGu8K57EeS5BEvq9KJQQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}